Nucleic acids 2

Question 1

It is formed by further organization of chromatin and chromatid and has two-fold symmetry at metaphase

Answer 1

Chromosomes

Question 2

⮞ It is an adenine-thymine (A-T) rich region

⮞ site where identical sister chromatids are connected

Answer 2

Centromeres

Question 3

⮞ centromere-protein complex

⮞ provides an anchor for mitotic spindle

Answer 3

Kinetochore

Question 4

⮞ contains altered nucleosome structures

⮞ DNA in these regions are susceptible to “DNase I” digestion

Answer 4

ACTIVE REGIONS

Question 5

Type of point mutation with NO changes in amino acid and is at 3RD base of codon

Answer 5

Silent type

Question 6

What is the chromatin composed of?

Answer 6

⮞ DNA
⮞ RNA
⮞ histones
⮞ non-histone proteins

Question 7

⮞ It is a complex of certain histones

⮞ DNA that looks like rosary beads

Answer 7

Nucleosome

Question 8

H1 phosphorylation: chromosome condensation

general core histone acetylation: ___________

Answer 8

chromosome assembly

Question 9

What is the associated process for ADP-ribosylation of histones?

Answer 9

DNA repair

Question 10

What is the associated process of Histone Methylation?

Answer 10

activation and repression of gene transcription

Question 11

H3 and H4 Acetylation 🡆

Answer 11

Inactivation/activation of gene transcription

Question 12

What is composed of two of each of CORE HISTONES?

Answer 12

histones octamer

Question 13

Significant function of Histone Chaperones?

Answer 13

It facilitates chromatin assembly factors

Question 14

A constitutive heterochromatin is essentially INACTIVE because

Answer 14

it is always condensed (if chromatin is condensed, access by transcription enzyme is limited)

Question 15

Site of enhancers for binding transcriptional activator proteins in DNA

Answer 15

Active regions

Question 16

Region rich in 5-methyldeoxycytidine

Answer 16

Inactive regions

Question 17

What do you get when you unpack chromosomes?

Answer 17

dsDNA (double-stranded DNA)

Question 18

Type of RNA: cellular machinery for protein synthesis

Answer 18

Ribosomal RNA (rRNA)

Question 19

Type of RNA: adapter for translation of RNA into specific sequences of amino acids in peptides/proteins

Answer 19

Transfer RNA (tRNA)

Question 20

Denaturation of DNA: leads to an increase in absorbance of purine and pyrimidine bases

Answer 20

Hyperchromic shift (remember: absorbance = concentration)

Question 21

In terms of denaturation of DNA, increasing the temperature means you increase

Answer 21

ENTROPY (thus disruption of H-bonds)

Question 22

What trinucleotide sequence leading to Fragile X syndrome?

Answer 22

CGG

Question 23

this trinucleotide CGU means

Answer 23

Arginine

Question 24

this trinucleotide CTG leads to

Answer 24

myotonic dystrophy

Question 25

this trinucleotide CAG leads to

Answer 25

huntington’s disease
spinobulbar muscular atrophy
kennedy disease

Question 26

What describes a PSEUDOGENE?

Answer 26

processed genes containing non-sense codons